Old Sears Rototiller Project

Mon Jun 06, 2011 3:36 pm

I'm trying to get this old Sears 14/28 ROTO-SPADER going.It has front tines, (that won't bend digging loose sand), and a two-speed tilling gearbox (HI-LO) with reverse also.It ran a bit last year after I tinkered with it after it sat for about 5 years. Now it has no spark at all.I know I have a good plug, it runs a mower when I put it in there.Does anybody have the troubleshooting steps and tune-up specs for this to share?Where to find genuine B/S Igntition parts?It's an 8HP Briggs. Model # 190402.Type 0858-01.Code 750 210 11Nobody makes behemoths like this anymore, and I need to get it working.Thanks guys!

Re: Old Sears Rototiller Project

Mon Jun 06, 2011 4:25 pm

No spark.

Trace the wire from the magneto to ground. See if the wire is grounded/shorted out. Grounding out the wire functions as the kill switch. Spark plug removed. Spin engine over - checking for spark.

Remove the shroud. Clean up the magnets on the flywheel and clean up the lower (towards flywheel) ends of the magneto. Readjust the gap between the magneto and magnets. Spark plug removed. Spin engine over - checking for spark.

Still no spark - pull the flywheel to access to the points.

Edit: B&S parts - local autoparts store.

Re: Old Sears Rototiller Project

Tue Jun 07, 2011 6:56 am

Eugene, I already did all that!I dunno if there's any way to test these ignition parts or not.I did find a Plug/Points/Condenser Kit for $14, I'll go get that I suppose and start there.A new Coil is $45 ! ! !All electrical parts are non returnable the counter guy says....

Re: Old Sears Rototiller Project

Yup. Another thing is that the brand new out of the box magneto coil may not work. Frustrating and expensive to have to go through several new coils to find one that works.

If you have pulled the flywheel, you can use your multimeter to check the points, condensor (indication of condition only) and the coil for shorts.

I am now salvaging out magneto coils and carburetors from junk small engine.

Next thing, for stationary applications I convert the magneto over to battery powered ignition systems.

Re: Old Sears Rototiller Project

Tue Jun 07, 2011 10:01 am

For me, the problems with the older Briggs engines getting spark has been the points. I just pull the flywheel and clean the points with a file or sandpaper. Make sure the aluminum key is intact and check the wires for bare spots or open wires. It should work if the coil is good.

Briggs switched to a transistorized ignition coil and can be retrofitted to engines of that era. This will eliminate the points and condensor, just a bolt/screw on of the new coil to where the old coil attached. If your coil is bad then that likely is the best way to go but I have Briggs engines from the 1930's on up and have yet to have a bad coil. The Bendix coils from older Kohler engines did crack but the Briggs coils were reliable. Possible but I would double check the points cleanliness, setting, continuity as well as the capacitor check. Make sure the points are moving when you turn the shaft, the small fiber plunger can stick and hold the points open. I also cannot think of a Briggs engine that I have had to replace the points, just a good cleaning may work.

If you decide to replace the coil with a new solid state coil be aware that the coil depends on a certain order for the magnet polarity. Yours should be OK since it is not that old but you can check the comaptibility of the magnets on the Briggs website for sure.

Re: Old Sears Rototiller Project

Sat Jun 11, 2011 7:32 am

After looking at the prices for the points, condenser and coil...and the fact that nobody close to me had the coil in stock, I did decide to go ahead and purchase the new electronic unit. I saved some money in the process as well! It was simple to install, and the tiller fired right up! After a few hours, the garden is ready to put in...now, where's that bottle of advil at???...

Re: Old Sears Rototiller Project

Sat Jun 11, 2011 9:17 am

Marion(57 Loboy) wrote:I did decide to go ahead and purchase the new electronic unit.

What is the part number for the electronic unit and where did you purchase it? Thanks.

Re: Old Sears Rototiller Project

Sat Jun 11, 2011 8:32 pm

For my 8HP Briggs, it was Part #398811. It is a Genuine Briggs Part.I purchased it at one of the local lawn and garden equipment stores, Doc's in Massillon Ohio.http://www.docslawn.com/They make several, including twin cylinder versions.Your engine may take a different one. Just take the Model and Type Numbers with you, they need those to cross reference.I've tilled up 3 gardens since I got mine running and it runs like a champ.

Re: Old Sears Rototiller Project

Sun Jun 12, 2011 9:26 am

Marion(57 Loboy) wrote:For my 8HP Briggs, it was Part #398811. It is a Genuine Briggs Part.

For future reference, 398811 cross references to 7-01643. The part number used by NAPA and other parts stores.

In the parts catalog, parts numbers in the 7-01602 thru 7-01652 series are replacement coils.